When a second line service (“SLS”) provider offers a method for routing calls between an SLS subscriber's telecommunications device (“TD”) and a third party's TD, the method may involve using a common relationship number associated to (1) the SLS number of the SLS subscriber, (2) the primary phone number (or any phone number from which the SLS subscriber can make/receive a call) and (3) the primary phone number of a third party (or any phone number from which the SLS subscriber can make/receive a call). In the typical SLS scenario, an SLS based call or communication is initiated from the TD of an SLS subscriber, and directed toward a particular third party or other final destination by the SLS subscriber entering or selecting the relationship number, directly or indirectly. These SLS based call or communications are routed to an SLS platform or server and then redirected by the SLS platform or server to a third party TD that is identified or associated with the relationship number. More specifically, the SLS leverages the relationship number such that the SLS call is routed to the SLS platform or server. At the SLS platform or server, the combination of the phone number associated with the subscriber TD used to initiate the SLS based call, and the relationship number identified in the SLS call, allows the SLS platform or server to identify the third party or the ultimate destination number. The SLS platform is then able to route the SLS based call to the third party number for call completion.
Unfortunately, it is not always possible for an SLS platform to determine the phone number associated with the subscriber TD used to initiate the SLS based call. In certain circumstances the call signal channeled through the telecommunications network handling the call or communication may not include sufficient information, such as the calling line identification (“CLID”) or any other data necessary to identify the phone number associated with the TD initiating the SLS based call. This missing CLID data may be the result of the telecommunication network, or its associated elements, not making the information available, not making the information reliably available, not making the information consistently available, etc. For example, when an SLS subscriber is roaming to a telecommunications network different from its primary, or “home,” telecommunications network, the CLID may not be available.
Regardless of what causes the CLID to be missing, the SLS platform or server cannot identify the third party or destination number at which to terminate the SLS based call if it does not have the subscriber TD's CLID. Accordingly, what is needed is a system and method for providing an SLS to a subscriber TD when the subscriber TD's CLID is missing.